Bug 198399
| Summary: | No display output on Tegra Acer Chromebook 13 starting with 4.14 | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Matías Zúñiga (matias.nicolas.zc) |
| Component: | IOMMU | Assignee: | drivers_iommu |
| Status: | RESOLVED CODE_FIX | ||
| Severity: | normal | CC: | kwizart |
| Priority: | P1 | ||
| Hardware: | ARM | ||
| OS: | Linux | ||
| Kernel Version: | 4.14 | Subsystem: | |
| Regression: | Yes | Bisected commit-id: | |
| Attachments: |
Oops with kernel 4.14.11
System log for a failing kernel System log for a working kernel |
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Created attachment 273473 [details]
System log for a failing kernel
Created attachment 273475 [details]
System log for a working kernel
when it works, i get lots of "iommu: Adding device *name* to group *number*"
FYI, there are few patches pending to disable arm implicit iommu conflicting with iommu handled by tegra: https://github.com/grate-driver/linux/commit/7f0750065a31ae491278a8960c1aceb4a44b847f (see also the others for tegra devices on the grate-driver/linux tree) Hopefully this can be fixed by 4.20 This has been fixed for some time (at least a year) |
Created attachment 273471 [details] Oops with kernel 4.14.11 Starting with kernel 4.14, there is no display output on the Acer Chromebook 14. I get a KERNEL BUG at exynos-iommu.c:743, exynos_iommu_domain_alloc (even though this device has a Nvidia Tegra K1) Reverting commit 928055a01b3: "iommu/exynos: Remove custom platform device registration code" makes it work again. I have the Oops message and system logs for a working and a failing kernel (the failing one is with kernel 4.14.10 because new versions came out while bisecting, but the bug still exists with the last version)